1. Field of the Invention
The present invention relates to biometrically authenticated access control in which a wireless authorization signal is sent from a portable unit, such as a key fob, after a biometric sensor on the portable unit has verified the identity of the user.
More specifically, the present invention relates to radio frequency identification (RFID) technology used in such devices.
2. Description of Related Art
Radio Frequency Identification (RFID) systems use an RFID reader to wirelessly detect the presence of a nearby RFID tag and read an identification code stored in the tag. The identification code in the RFID tag can be used to control access to a protected resource by allowing access only when an RFID tag having an authorized identification code is detected. Generally, the authorized RFID tag is issued to an authorized user to ensure that only the authorized user has access to the protected resource. If the authorized RFID tag is lost or stolen, however, it can be presented by an unauthorized user to access the protected resource.
One exemplary use for RFID tags is to install them in a key fob associated with one or more conventional mechanical keys. An RFID tag reader is then positioned near a lock system operated by a mechanical key kept on a ring with the key fob. To open the lock system, the correct mechanical key must be used, and an authorized RFID tag must be detected by the nearby tag reader.
To ensure that the RFID tag is in the possession of the authorized user to whom it was originally issued, newer designs for RFID access control systems have added a biometric sensor. The sensor, such as a semiconductor-based fingerprint reader, is located in a portable unit, such as a key fob, that contains an RFID engine to simulate the presence of an RFID tag. The biometric sensor includes a stored template of the authorized user's fingerprint.
The present state of the art in this field uses an RFID engine specifically designed from generic logic elements to simulate the operation of an RFID tag used with an existing RFID system. Such a system is provided by Privaris, Inc. of Charlottesville Va., which offers both key fob designs and smart card designs with an RFID engine simulating an RFID tag and an integrated fingerprint reader for biometric verification.
There is a large installed base of non-biometric RFID systems made by such companies as HID Corporation of Irvine Calif., Indala Corporation of San Jose Calif. and others that would benefit from the additional layer of security provided by biometric authentication. The presently available installed RFID systems use a variety of different complex coding and signaling methods, some of which are proprietary. The RFID tags used with these systems take two forms—cards and key fobs. In both cases the coding of the tags is done in a conveyor belt form where the tag moves past a programming/verification head where the RFID identification code is put in under the control of a computer. The code is specified by the customer from a very large range of options.
In general these companies do not allow third parties to program the RFID tags used with their RFID system except in the case of using certain leased card programmers which are provided to trusted distributors for use with RFID tags that they provide to their customers. The coding that these leased programmers can embed is limited to certain specific ranges and formats allowed by each of the distributors and controlled by an encrypted media, which is supplied by each of the companies.
There is also a non-proprietary, non-controlled format available, which is known as “26 bit wiegand.” This format is not recommended for high security applications and is not appropriate for use where biometric verification is used as a secondary layer of security.
The proprietary nature of the coding and signaling of existing installed systems, the restrictions on programming, as well as technical considerations make it difficult to simulate the operation of existing proprietary RFID tags with an RFID engine constructed from generic logic elements. Owners of proprietary RFID systems are often unwilling to disclose details of the proprietary system that are needed for simulation in an RFID engine.
Moreover, even where such information is available, the programming procedure for an RFID engine simulating an RFID tag may be incompatible with the installed base of programmers used with the proprietary system. There is a need for a portable biometrically authenticated RFID device, such as a key fob, that uses a securely integrated authorized RFID tag of an existing prior art type, instead of a simulation of such a tag in an RFID engine. Such a device could be securely programmed in existing RFID programmers and distributed and controlled by the owner of the proprietary RFID system using existing channels and methods.
Bearing in mind the problems and deficiencies of the prior art, it is therefore an object of the present invention to provide a biometrically authenticated access device that is compatible with and programmable by an existing installed base of RFID tag programmers.
It is another object of the present invention to provide a biometrically authenticated access device that has a relatively low manufacturing cost.
Still other objects and advantages of the invention will in part be obvious and will in part be apparent from the specification.